Abietate modified polysulfide polymers and other resins as adhesive additives for liquid polysulfide polymer based adhesive compositions

ABSTRACT

Polysulfide and polyester polymers modified with abietic acid are effective as adhesive additives for liquid polysulfide polymer based compositions used as sealants or bonding agents on various substrates such as glass or aluminum.

United States Patent [1 1 Villa I ABIETATE MODIFIED POLYSULFIDE POLYMERSAND OTHER RESINS AS ADHESIVE ADDITIVES FOR LIQUID POLYSLTLFIDE POLYMERBASED ADHESIVE COMPOSITIONS {62] Diusmnul'ser No 252.646 Ma) 12.I971P1ILNO [52] US. Cl v 260/26: ll7/l24 E: ll7/l32 R;

260/24; 260/312 R; 260/318 R. 260/37 R: 260/75 S; 260/79; 260/791;260/823; 260/830 R; 260/830 S: 260/860; 260/873 [lll 3,919,147

[ Nov. 11, I975 [5l] Int. Cl. A. C(l8g 17/16 [58] Field of Search260/79. 79.l. 26 S73 [56] References Cited UNITED STATES FATE NTS 3/1966Calduell et alumni. i 260/36 Primary E.\umi/wrMel\}'n l MarquisAttorney, Age/11, 0r FirmStanle A, Marcus; Thomas W Brennan [57]ABSTRACT Polysulfide and polyester polymers modified with ahi etic acidare effective as adhesive additives fur liquid polysulfide pol} merbased compositions used as sealants 0r bonding agents on varioussubstrates such as glass or aluminum 2 Claims. N0 Drawings ABIETATEMODIFIED POLYSULFIDE POLYMERS AND OTHER RESINS AS ADHESIVE ADDITIVES FORLIQL'ID POLYSL'LFIDE POLYMER BASED ADHESIVE COMPOSITIONS This is adivision of application Ser. No. 252.646 filed May 12. 1972 now US. Pat.No. 3,813.368.

BACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates to improved liquid poly'sulfide polymer based adhesivecompositions containing novel adhesive additives. More particularly thisinvention relates to improved liquid poly sulfide polymer based adhesivecompositions containing novel adhesive additives prepared by modifyingpolysulfide and polyester polymers with abietic acid and poly'sulfidepolymers with epoxy groups.

2. Description of the Prior Art Curable. liquid polysulfide polymerbased sealant and caulking compositions have long been known in the art.They are based on curable, liquid, mercaptan terminated polysulfidepolymers. The structure and preparation of these polythiopolymercaptanpolymers are disclosed in U.S. Pat. No. 2,466.96 These liquid. mercaptanterminated polymers are used extensively in sealant and caulkingcompositions, especially in the building, automotive, and marineindustries; for eastings. e.g.. solid rocket propellants; for leatherand textile impregnating agents; for adhesives. coatings, etc. Becauseof the wide range of applications in which these polysulfide polymerbased sealing and caulking compositions are used, they must be capableof bonding to various substrates, e.g., metal, aluminum, glass.concrete. wood, etc. However, the adhesive qualities of polysulfidepolymers are such as to usually require the use of an adhesive additivein the polysulfide polymer based sealant composition in order to insureadequate bonding of the cured sealant to the substrate.

Adhesive additives of the prior art such as those of a phenolic natureprovided only a polar, rather than a chemical, type bonding of the curedsealant to the substrate. Thus, sealant compositions containing phenolictype adhesive additives were found to be susceptible to attack by polarsolvents such as water. The polar solvent tended to break down the polarbond thereby impairing the utility of the sealant composition. Morerecently, as disclosed in U.S. Pat. Nos. 3,297,473; 3.312.669. and3,328,451, certain organo-silanes e.g., (mercapto alkyl amino alkylalkoxyl silanes) have been proposed to overcome these problems. However,while the organo-silane adhesive additives have been found to protectthe sealant composition bonds from attack by polar solvents, they dohave certain disadvantages. Thus. the organo-silane adhesive additivesare econom ically costly, somewhat deficient in storage stability, andexhibit erratic adhesion results with certain substrates, such asconcrete.

The object of the present invention, therefore. is to provide a novelliquid polysulfide polymer based caulking or sealant composition whichwill allow for the attainment of a strong and lasting bonding of thesealant to the substrates to be treated therewith.

Another object of the present invention is to provide a novel liquidpolysulfide polymer based caulking or sealant composition containingadhesive additives which are less costly, exhibit improved storagestability.

2 and which exhibit more reproducible and uniform ad hesioncharacteristics to a wider range of substrates.

Other objects of the invention will become apparent to those skilled inthe art from a consideration of the following detailed description.

SUMMARY OF THE INVENTION lt has now been unexpectedly found that theobjects set forth above can be accomplished by the use of an abietateterminated poly sulfide polymer, an abietate terminated polyesterpolymer, or an epoxy terminated polysulfide polymer as an adhesiveadditive for the liquid polysulfide polymer based sealant composition.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As indicated previously, thenovel adhesive additives of the present invention are the abietateterminated polysulfide polymers, the abietate terminated polyesterpolymers, and the epoxy terminated polysulfide poly mers. Of theseadhesive additives, the abietate terminated polysulflde polymers arepreferred because they exhibit more uniform and reproducible adhesionresults to various substrates when incorporated into a liquidpolysulfide polymer based sealant composition The abietate terminatedpolyester polymer and epoxy terminated polysulfide polymer adhesiveadditives show increased adhesion to certain substrates. However, it hasbeen found that larger quantities of these latter adhesive additives arerequired to produce increased adhesion results. The use ofthese adhesionadditives in the required quantities often results in some retardationof the cure rate of the sealant composition. Moreover, adhesion resultson the abietate terminated polyester polymer and epoxy terminatedpolysulfide polymer adhesive additives have not proven to be as uniformnor as reproducible as the preferred abietate terminated polysulfidepolymer adhesive additive. For that reason, it is recommended that theabietate termi nated polyester polymer and epoxy terminated polysulfidepolymer adhesive additives be used at not more than 5 parts by weight ofadditive per parts by weight of liquid polysulfide polymer based on thetotal weight of the sealant composition. Larger quantities of theseadhesive additives may require an adjustment in the amount of curingagents employed.

The abietate terminated polysulfide polymer adhesive additive of thepresent invention may be prepared by reacting a relatively low molecularweight, e.g.. 500 to 4000, preferably 500 to 1500, SH terminated liquidpolysulfide polymer (hereinafter referred to as a liquid polythiolpolymer) with abietic acid at temperatures of from C. to 200C. Thereaction is preferably carried out in a solvent medium and under aninert atmosphere.

The liquid polythiol polymer used as the starting material for reactionwith the abietic acid may include those polythiopolymercaptan polymersas are disclosed in U.S. Pat. No. 2,466,963 and which may be representedby the formula HS(RSS),,RSH where R is a hydrocarbon, oxahydrocarbon orthiahydrocarbon radical such as the ethyl formal radical (CH CH -OCH-O-CH CH the butyl formal radical and n will vary from about 4 to 23.

A preferred liquid polythiol polymer will have a molecular weight of 500to 4000. A particularly preferred liquid polythiol polymer used in thepractice of the present invention is a liquid polythiol polymercontaining no crosslinking and having a molecular weight of 1000.

While the reaction between the liquid polythiol polymer and abietic acidis not known with exact certitude. it is theorized that the reactionproceeds with inversion of a mercaptan terminal to a hydroxyl terminalfollowed by esterification. The reaction is believed to pro ceed in thefollowing manner;

asc 11 -o-ca -o-c a -ss OOC CH 3 3 CH(CH3)2 wherein n will vary from 4to 23.

As indicated previously. the reaction product of the liquid polythiolpolymer and abietic acid is believed to be predominantly of the generaltype structure shown above. However. it should be observed here that thereaction product may in fact contain a mixture of chemical structures.Thus. it is likely that in addition to the above structure. the reactionproduct may contain additive may be incorporated into the liquidpolysulfide polymer based sealant composition in amounts of from 0.5 to3.5 parts by weight per 100 parts by weight of liquid polysulfidepolymer.

The abietate terminated polyester polymer adhesive additive may beprepared by any of several procedures. For example. a hydroxylterminated liquid polyester polymer of relatively low molecular weighte.g. 500 to 2500. preferably 500 to 1500. may be reacted with abieticacid under an inert atmosphere at temperatures ranging from about l40C.to 200C. with or without the presence of a solvent. Alternatively. theindividual components which react to form the hydroxyl-terminated liquidpolyester polymer may be directed admixed with the abietic acid in asuitable mixing apparatus and then reacted to form the abietateterminated polyester polymer used as the adhesive additive in thecompositions of the present invention.

The hydroxyl-terminated liquid polyester polymers which may be reactedwith abietic acid to form the abietatc terminated polyester polymeradhesive additives of the present invention may be virtually any ofthose known to the art. These hydroxyl-terminated liquid polyesterpolymers may be prepared in known manner by reacting diols or polyolswith dicarboxylic or polycarboxylic acids under temperature and pressureconditions known in the art. Typical dicarboxylic acids useful inpreparing the polyesters include oxalic. adipic. azelaic. sebacic,maleic, and fumaric acids and others. as well as mixtures of theseacids. The diols used may include ethylene glycol, diethylene glycols,alkane diols. castor oil and the like. As indicated previously. theliquid polyesters preferably have a molecular weight of 500 to 2500.

Liquid polyester polymers containing sulfur in the polyester moleculeare particularly preferred in the practice of the present inventionsince they are believed to be more compatible with the liquidpolysulfide polymer of the sealant composition. A preferred abietatemodified sulfur containing polyester polymer adhesive additive of thepresent invention may be prepared by mixing and reacting thiodiethyleneglycol. azalaic acid. maleic anhydride. and abietic acid under an inertatmosphere at a temperature of l30C. to 190C. The resulting abietateterminated polyester polymer adhesive additive may be incorporated intothe liquid polysulfide polymer based sealant composition in amountsranging from 0.5 to 5.0 parts by weight per l00 parts of liquidpolysulfide polymer. At the higher concentration some retardation of thesealant composi tion cure rate is observed.

The epoxy modified polysulfide polymers used as adhesive additives inthe compositions of the present invention may be prepared by reacting arelatively low molecular weight e.g. 500 to 4000. preferably 500 tol500. liquid polythiol polymer. such as the liquid polythiol polymerdescribed previously. with a diepoxide such as vinyl cyclohexanediepoxide in a solvent medium in the presence of an acid catalyst. Thechemical reaction between the liquid polythiol polymer and vinylcyclohexane diepoxide is theorized to proceed as follows:

where R is the ethyl formal radical tCH -CH OCH OCH CH and u may varyfrom 4 to 23.

In the above reaction. the epoxy cyclohexane group is reactive underacidic conditions whereas the epoxy ethyl group is reactive under basicconditions. The chemical structure shown above is believed to be thepredominant form of the reaction product. However. it should be observedthat the reaction product very possibly may consist of a mixture ofmaterials with varying structures. Thus. it is possible that thereaction product in addition to the above structure may contain aproduct wherein the polysulfide polymer has an epoxy terminal at bothends of the polymer chain or a portion of the reaction product has SHterminals at both ends of the polymer chain.

A particularly preferred epoxy terminated polysulfide polymer adhesiveadditive of the present invention is prepared by reacting a liquidpolythiol polymer of 1000 molecular weight having no erosslinking withvinyl cyclohexane diepoxide in a solvent medium in the presence of anacid catalyst.

The reaction product of a liquid polythiol polymer and a diepoxide is anepoxy terminated polysulfide resin which can be incorporated into theliquid polysulfide polymer based sealant composition in an amountranging from 0.5 to 5.0 parts by weight of epoxy terminated polysulfideresin per l00 parts by weight of polysulfide polymer. At the higherconcentration of adhesive additive. some retardation of sealantcomposition cure rate is observed.

The liquid polysulfide polymers which form the polymer base of thesealant or caulking compositions with which the novel compounds of thepresent invention are used as adhesive additives are those liquidpolythiopolymercaptan polymers as are disclosed and claimed. as notedabove. in US. Pat. No. 2.466.963. The most preferred of such polymersfor the purposes of making sealant or caulking compositions are thosehaving a molecular weight of about 500 to 4000.

The liquid polysulfide polymer curing agents which may be used insealant compositions with the novel adhesive additive compounds of thepresent invention include all those materials known to the art as liquidpoly-sulfide polymer curing agents such as poly-epoxy resins. leadperoxide, calcium peroxide. zinc peroxide. lithium peroxide. bariumperoxide. tellurium dioxide and the various chromate salts as aredisclosed in US. Pat. No. 2.964.503. In addition. as disclosed in USPat. No. 3.487.052 various other inorganic oxides and peroxides. organicperoxides. permanganates. organo tin compounds. organic nitro compounds.and quinoid compounds can often be advantageously used as curing agentsof said liquid polysulfide polymers. About 2 to l0 parts by weight ofone or more of such curing agents should be used in such compositionsper I00 parts by weight of liquid polysulfide polymer being used.

Curable liquid polysulfide polymer based sealant compositions used inconjunction with the adhesive additive compounds of the presentinvention may also contain various types of inert materials commonlyemployed in liquid polysulfide polymer based sealant compositions suchas fillers. plasticizers. pigments. ultraviolet light stabilizers. cureaccelerators. and the like.

The substrates which can be treated with sealant compositions containingthe novel adhesive additives of the present invention include those of awood nature, those of a silicaceous nature such as glass. those of ametallic nature such as aluminum. iron, and steel, and to a limiteddegree concrete.

in order to illustrate further the nature of the present invention, thefollowing examples are submitted. These examples are merely illustrativeof the present inven- 6 tion and are not intended as a limitation uponthe scope thereof.

EXAMPLE 1 Preparation of Abietate Terminated Liquid Polysulfide PolymerResin A 4000 ml. resin kettle equipped with a Barret trap. a thermometerand adapter. an electric stirrer. a gas inlet tube and a Fredric kscondenser was charged with 2000 grams (2moles) of a liquid polythiolpolymer of 1000 mol. weight having no crosslinking. 604.88 grams (2moles) of abietic acid. and 150 mls. of xylene. The mixture was heatedunder a nitrogen atmosphere for approximately 1 hour 15 minutes at whichtime the temperature had reached l90C. and I0 mls. of H 0 had collectedin the Barret trap. The mixture was then heated for approximately 2V2hours at l90C at which time 34 mls. of H. ,O had collected in the trap.The mixture was heated for an additional l0 minutes and the heat thenremoved. A sample of resinous product was removed from the resin kettleand analyzed for SH percentage. SH percent was found to be 2.7% The nextmorning. heat was again applied to the mixture for ap proximately 2hours at I65C. An additional 6V2 mls. of H 0 collected in the trap for atotal of 41 mls. of H 0 collected and removed during the reaction. Heatwas removed at this time and a sample of resinous product analyzed forSH percentage. Analysis indicated that SH percentage was 0.5% A vacuumwas hooked up to the reaction apparatus and the reaction was heated toC. until all the xylene had been evaporated. The resinous abietateterminated polysulfide polymer was collected and the acid number andhydroxyl number determined. Results were as follows:

I. Acid No. OH No. 1. 39.245 ins-u 3. 39.14 13:49

About 5.5 pounds of abietate terminated polysulfide polymer resin wasprepared by the above procedure and used as an adhesive additive in theexamples which follow.

EXAMPLES 2-4 Ingredients Parts by Weight LP-32 Polysulfide Polymer I001)Multiflex MM (Calcium Carbonate] 25.0 lcecap R (Anhydrous C lay) 30.0Titanox RA 50 (Titanium Dioxide) 10.0 Arochlor I254 (ChlorinatedDiphenyl) 35.0 200.0

LP-32 polysulfide polymer has essentially the structure HS-l C;.H.OCH-,0-C .H.-SS),,C;,H.O-CH,OC H.SH with about 0.5; cross'linking and amolecular weight of about 4000.

A control formulation (Example 2) for this evaluation was prepared bycombining the above sealant masterbatch with a lead peroxide curingpaste (described hereinafter). One test formulation (Example 3) wasprepared by combining the sealant masterbatch with the abietateterminated poly sulfide polymer resin and a lead peroxide curing paste.An additional test formulation (Example 4) was prepared by combining thesealant masterbatch with the abietate terminated polysul continuedPolysult'ide Sealant Masterhatch Parts by eight Thixein (iR (thixotropicagentl lltl) As indicated previously. the above sealant masteri h 2 iLumflg i batch was combined with the abtetate terminated poly- ..,t a Iscrt LL. t ctl'lctnt ter L Lontro tnt test ormu attons Sulfide pMymcrrcsm and a calcium pcmxlde Curing O paste to form the test formulation.The test formulation is shown below. Parts by eight lormulation Ex .\o I4 Polysulfide Sealant .\l'.tsterbatch "(IIHI 3mm 2mm Polysull'ltleSealant Test Formulation Abtetate lerminated Polysult'ttle IngredientsParts by Weight Polymer Adhcsin ALldill\L l.ll l .U L l P qd i i Push;|S s u Polysult'lde Sealant Masterbatch 125.0 Zine Peroxide (tiringPaste 33 l) Abietate l'erminated Polysulfide Polymer Resin l.() 3t]('aleium Peroxide Curing Paste 37.5

The lead peroxide curing paste shown above is a mix- Th b l Uri St mhwren L ture ot lead peroxide and aroehlor 1254 containing l perm g F s; oiCaO. Tttanox RA 50. Calcium Hvclroxtde. and Aro- U.r PbO:. Arochlor l -4ts a chlorinated dtphenxl r x s chlor i254 containing 26.7/( CaO.,,l3.3/ Titanox RA plasttctzer. The llnC PLfUfxtLlC curing paste shown Q 667 C I H I d W 47 A h] r above is a mixture of zinc peroxide. arochlori354. and I mum me 0 amax containing 45.5% ZnO. 45.592 arochlor [254. At d l th b f l w and 9G amax. Amax is n-oxy-diethylene benzothiozolet d6 l E 6 s 3? a as Z-sulfamide and is used as a cure accelerator. J i igl t l g i gs Peel adhesion strength specimens bonded to glass f l m 65es S 5 0 and aluminum substrates were prepared from the l e aboveformulations. These specimens were exposed to TABLE II 7 da ys in air atroom temperature. 7 days ll] an oven at Adhesim Peel snengh mes (PSI,

[5b F.. and 7 days immersion Itl room temperature wa- Substrate ter.Peel adhesion valves were obtained upon removal l Alumnum Example Test lTest 2 Test 1 Test 2 of the specimens from water immersion whtle thesamples were still wet using an lnstron tester. The results of 5 3 thepeel adhesion tests are shown in Table I.

TABLE l Adhesion Peel Strength \"ahes lPSll Evaluation of The Effect ofThe Abietate Terminated (Jlass Aluminium bump. Tm 1 TN 3 1 3 PolysulfidePolymer Resin on the Storage Stability of a w 3 column NA XA \A NA T oPaclt tge Polysulfide Polymer Based Sealant Corn 3 5: 54 :s :s POSIUOKI4 4b 53 $1 in these examples. the effect of the abietate termiu M ammo"nated polysulfide polymer resin on the storage stability The controlspecimens showed eom lete adhesion failure to both the lass and of a twopackage sealnt composition was determined by admixing said resin withthe polysulfide sealant masterbatch used in examples 2-4 and then agingthe ad- EXAMPLE mixture in an oven for7 days at 158F. A sample of theabove oven aged admixture was then combined with Evaluation of TheAbietate Terminated Polysulfide lead peroxide curing paste to form onetest formulation Polymer Resin As An Adhesive Additive in at Liquid(Example 6) while an additional sample of the oven Polysulfide PolymerBased Sealant Composition Utiliz- 55 d d i t was bi d wi h zinc per xidecuring a Calcium Peroxide C urmg System. ing paste to form a second testformulation (Example In this example. the abietate terminatedpolysulfide 7). polymer resin was combined with the polysulfide seal-Specimens f th test f rmul tions bonded to aluminant masterbatch shownbelow. cured with a calcium ium and gla s ub trate were then repared forpeel peroxide Cur ng p e (deSCrlbCd m) d then adhesion strength tests inaccordance with the procetested for peel adhesion using the proceduredescribed dar de ribed in E am les 2-4. The test specimens in Examples2-4. were then aged for 7 days in air at room temperature,

7 days in an oven at 158F.. and 7 days immersed in room temperaturewater.

Polysulltde Sealant Masterbatth Parts by Weight In essence thisevaluation Serves to measure the f. LP-33 P b P b b HMO feet of hightemperature storage on a two package seal- Witcarb RC (precipitatedcalcium car onatel 40.0 r Gimme [wk-um curhmmm ant composition whereinthe abtetate terminated poly Titanox RA 5U (titanium dio\idet l().(l

sulfide polymer resin is incorporated into the liquid 9 polysulfidepolymer based sealant package. Thus. the test is also a measure of thestorage stability of the resin as an adhesive additive.

The test formulations and peel adhesion valves as determined on alnstron tester are shown in Table III.

TABLE [II Parts by Weight ing from 185C. to 200C. at which time a totalof approximately 64 mls. of H 0 had collected in the trap. At thispoint. the reaction mixture had been heated for a total of approximately8 hours. The reaction mixture was again permitted to stand overnight.The next mo rn ing heat was again applied to the reaction mixture andthe mixture heated for approximately 6 hours at temperatures of 150C. tol75C. at which time a total of hwmulmnm h h about ()6 mls. of H 0 hadcollected in the trap. At this i "*'"E time heat was removed and thereaction mixture al- Ahietate terminated polysultide l.ll l.U

PM), Min lowed to cool to l00C. A vacuum system was then 29*} t l f F lP f1 hooked to the reaction mixture apparatus and the reac- T tionheated at 150C. for 2 hours under 7 mm of Hg pressure to remove any H Oor solvent remaining in the resinous product. A sample of resin productwas analyzed for OH number and acid number with the follow- Pm gi i l fing results: OH number 13. l 1. acid number 37.40.

Glass h Aluminium 38.72. A total of 645 grams of abietate terminated Tm3 TN 3 polyester resin were produced during the reaction.

a is 77 2a is 7 4| 3 33 EXAMPLES 9-l2 Evaluation of Abietate TerminatedPolyester Resin As An Adhesive Additive in Polysulfide Sealant For- Theabove peel strength data indicates that the abietmulmions lermlq'dtedpol-lSulfide Polymer resin did not In these examples. the abietateterminated polyester l' P Strength adhesion "alues of the P resin ofExample 8 was evaluated at l and 5% levels in Sulfide Sew-1m Compositionmen when exposed high the polvsulfide sealant masterbatch of Examples2-4 temperature aging storage conditions. In fact, when uccordihg to thefollowing fmmulmions. compared to the peel adhesion values of Table Iwherein the same compositions were tested without 30 P1 1 b w i h prioroven aging of the sealant masterbatch. these ad- Fmmuhn-mn 5, N 9 ii; fir3 hesion results are equal to or better than the results polwumde Selhmmm) 0 mm) WI U shown therein. Thus. the abietate terminated polysulmtide polymer resin exhibits excellent storage stability. AhiswwTermiljlltsd 3s lUhQSePRtISli'I EXAMPLE 8 LLlglfxlmillfl'uUklfi Curing15.0 l .0 Preparation of Abietate Terminated Polyester Resin gf g CmlngAdhesive Additive A I000 ml. resin pot equipped with a Barret trap. athermometer and adapter, an electric stirrer, a gas inlet 40 to f th blsealants 8, 9, 10, d 11 Th above tubeand Fredencks condens'er F Wlthsealant compositions were appliedas beads in duplicate 299.20 grams(2.45 moles) of th odiethylene glytocleanunprimedglass,aluminum,andconcrete panels 165-35 grams (0-88moles) of 8602 grams and left to cure for 7 days in air at roomtemperature. moles) of male: anhydnder and WG-00 grams One set ofduplicates was tested for adhesion. The (0.56 moles) of abietic acid.The mixture was heated other Sgt of panels was the immersed in tap waterfor under a helium agmospheri for abou? hours at 7 days at roomtemperature and then tested for adheperatures of B0 to 150 at whl ch 29P sion. The adhesion tests consisted of attempting to peel H2O hadCollected P the The was pemm the cured sealant beads from thesubstrates. If the bead teddo a Overnight T T mormflg heat was could notbe removed without tearing the bead. this again applied to the reactionmixture and it was heated was noted as a cohesive failure. If the beadpeeled off it for 2 hours at whlch the temperature w lgooc' was noted asan adhesive failure. If the bead separated and atotal of mls. of H 0 hadcollected in the trap. during water immersion or if virtually no forcewas re At lhls tlmeapptoxlmafely 35 P Xylene were quired to remove thebead, it was noted as having no added to the reaction mixture. Themixture was then adhesion (NA). Results of these adhesion tests areheated for an additional 6 hours at temperatures rang- 55 Show in TableIV.

TABLE IV At the 5" le\el of adhesive addithe. the sealant compositionswere not completely cured.

Codei C==Coheshe Failure =Adhesi\e Failure NA -ko Adhesion The dataindicates that the sealant composition containing l'4 adheshe additiveand lead pcrovide curing agent (Emmple N) gaugootl adhesion to glass inboth the tilt and nater tests EXAMPLE 13 Preparation of Epoxy TerminatedPolysullide Resin Adhesive Additne A 500 ml. B necked RB flask equippedwith an air condenser. thermometer. stirring rod and mixer was chargedwith 100 mls. of Dioxane. 0.5 grams p-toluene sulfonic acid. 200 gramsof liquid polythiol polymer containing no erosslinking and having amolecular weight of 1000. and 59 grams of vinyl cyclohexane diepoxide.The reaction was designed to terminate when EXAMPLES l4l7 Evaluation ofEpoxy Terminated Polysultide Resin as an Adhesive Additive in aPolysulfide Sealant Composition.

ln these examples. the epoxy terminated polysulfide resin of Example 13was evaluated in the polysulfide sealant masterbatch of Example 2 at a land 5% level in the following formulations:

Parts by Weight a 50% reduction of the estimated SHk and epoxyFtflmlldliln Ev Ni 17 group i of the original reactants was obtained,The liqpomun-ldc 5mm 3001, mm utd polythiol polymer contained anestimated 6.4% SH Maswrlwtch and the \inyl cyclohexane reactantcontained an estiai -1ixawm 11! s u 1 u a mated .34? epoxy groups. Thereaction mixture was Lead 'Pemuat- Curing 15.1 15.1: k heated to C. for6 hours and minutes. At this P Line Peroxlde Luring 231) 22.1! time. thereaction mixture was heated to reflux at l 13C for 7 hours and 40minutes. During this period. the reaction mixture was sampled andanalyzed for SH% and epoxy "/z. Analysis of these groups showed lessthan 50% reduction in SH'I'E and epoxy J2. Accord ingly. the mixture waspermitted to stand overnight. On

Adhesions of the above curable formulations were run in accordance withthe procedure described in Examples 8-11. Adhesion results are shown inTable V.

TABLE V Conditions 7 Days in Air at Room Temp. 7 Days in Water SubstrateGlass Aluminum Concrete Glass Aluminum Concrete Example No. AdditheCuring Agent 14 l P paste A NA C NA NA NA 15 5* PhO paste C C C C C NAIf: l ZnO paste C NA C NA NA NA 17 5* 2110: paste C C C C C NA Someminor cure retardation noted at 5'1 le\el of addithe in both ZnO and PM)cured stocks Codex C=Cuheshe Failure A=Adhesive Failure NA=No AdhesionThe ahove data show s that the epoxy terminated poly sulfide adhesneadditne at the 5': le\el gaw excellent adhesion to glass and aluminumubstrates in bath the ZnO and PhO cured sealants and in both air and\tater adhesion tests.

the next day, heat was again applied to the reaction mixture and it washeated for an additional 6 hours at 1 1 1C. At this point. a sample ofreaction product was analyzed and 81-17: was found to equal 3.39% andepoxy percent was found to equal .17l7c. This indi- Now having fullydescribed my invention, 1 claim:

1. A curable. liquid. abietate-modified polysulfide polymer basedsealant composition containing as an adhesive additive, about 0.5 to 5.0parts by weight per 100 parts by weight of polysulfide polymer preparedby reacting a liquid polyester polymer having a molecular weight of from500 to 4.000 and abietic acid in a solvent at a temperature of C. to200C. under an inert atmosphere.

2. A curable, abietate modified sealant composition comprising in weightratio.

a. 100 parts by weight of liquid polysulfide polymer.

b. about 2.0 to 10.0 parts by weight of liquid polysul' cated anapproximate reduction of 50% in the original 50 fide polymer curingagent, and

SH and epoxy group percentages. The reaction mixture c. about 0.5 to 5.0parts by weight of the reaction was then placed in a rotor vacuum waterasperator and product of a liquid polyester polymer having a moa hotwater bath to evaporate the solvent. The experilecular weight of from500 to 2500 and abietic acid mental procedure yielded 211.2 grams ofproduct in a solvent at a temperature of C. to 200C. Total heating timeof the reaction mixture was about 20 55 under an inert atmosphere.

hours.

1. A CURABLE, LIQUID, ABIETATE-MODIFIED POLYSULFIDE POLYMER BASEDSEALEANT COMPOSITON CONTACINING AS AN ADHESIVE ADDITIVE, ABOUT 0.5 TO5.0 PARTS BY WEIGHT PER 100 PARTS BY WEIGHT OF POLYSULFIDE POLYMERPREPARED BY REACTING A LIQUID POLYESTER POLYMER HAVING A MOLECULARWEIGHT OF FROM 500 TO 4,000 AND ABIETIC ACID IN A SOLVET AT ATEMPERATUREOF 130*C. TO 200*C. UNDER AN INERT ATMOSPHRE.
 2. A curable,abietate modified sealant composition comprising in weight ratio, a. 100parts by weight of liquid polysulfide polymer, b. about 2.0 to 10.0parts by weight of liquid polysulfide polymer curing agent, and c. about0.5 to 5.0 parts by weight of the reaction product of a liquid polyesterpolymer having a molecular weight of from 500 to 2500 and abietic acidin a solvent at a temperature of 150*C. to 200*C. under an inertatmosphere.